Field of the Invention
The present invention relates to an image processing apparatus and an image processing method. In particular, the present invention relates to an image processing apparatus, an image processing method, and an imaging apparatus, which can perform a face detection function in moving image processing.
Description of the Related Art
Conventionally, there have been known technologies including face detection processing for detecting a human face in an image, face recognition processing for recognizing a person of the detected face, and facial expression determination processing for determining a facial expression of the detected face. If the image includes a blocked up shadow area or a flared highlight area, the above-mentioned processings cannot be performed accurately for the area.
Therefore, in Japanese Patent Application Laid-Open No. 2009-278155, there is disclosed a method of generating a plurality of moving image signals of different exposures in face detection in moving image photographing and performing the face detection based on each moving image signal, thereby preventing a face from being not detected due to photographing against light or the like.
However, reading-out of a plurality of frames of different exposures and further performing the face detection processing on each of the plurality of frames result in increase of the number of frames on which the face detection processing and the like are performed, and hence time necessary for completing the processings is increased.
Here, as described in Japanese Patent Application Laid-Open No. 2011-23985, there has been known a technology of generating one frame image signal having reduced blocked up shadow areas and flared highlight areas by combining a plurality of image data of different exposure amounts. By performing the face detection processing, the face recognition processing, or the facial expression determination processing using a frame image signal of broader dynamic range generated by combining a plurality of read-out frames, it is possible to obtain a processing result with high accuracy using one frame image signal.
However, the face detection processing, the face recognition processing, or the facial expression determination processing is performed after combining the plurality of image data of different exposure amounts. Therefore, the time necessary for obtaining a result of the processing increases compared to the case where the combining process is not performed, though the increase is not as large as in the case where the face detection processing or the like is performed on each of the plurality of frames.